偶氮苯-离子液体复合材料的光热储能性能分析

Analysis of photothermal energy storage performance of azobenzene-ionic liquid composites

采用溶剂共混法制备了复合材料C_(12)Azo-C_(12)VIM[Br],通过^(1)H NMR、XRD、DSC、UV-Vis等手段表征了复合材料的光致液化、相变温度、光致异构和光热焓值。结果表明,C_(12)Azo光致异构可诱导C_(12)VIM[Br]产生等温固液相变,而C_(12)VIM[Br]通过减少C_(12)Azo分子间的π-π堆积加速了C_(12)Azo的反式-顺式(trans-cis)光致异构转变速率,复合材料的总焓值ΔH_(total)包含相变焓ΔH_(PC)和光热焓ΔH_(PT),提高了体系的光热储能性质,其中7C_(12)Azo-3C_(12)VIM[Br]的总焓值为103 J/g,光热焓的转化效率E_(PT)为40%。

The composite materials C_(12)Azo-C_(12)VIM[Br]were prepared by solvent blending method.Using ^(1)H NMR,XRD,DSC,UV-Vis and other methods,the photoliquefaction,phase transition temperature,photoisomerization and photothermal properties of the composite materials were characterized.The results showed that C_(12)Azo induced the isothermal solid-liquid phase transitions of C_(12)VIM[Br].C_(12)VIM[Br]accelerated the photoisomerization rate of C_(12)Azo in composites by reducing the intermolecularπ-πstacking.The total enthalpyΔH_(total) of the system contained phase transition enthalpyΔH_(PC) and photothermal enthalpyΔH_(PT).The total enthalpy of 7C_(12)Azo-3C_(12)VIM[Br]was about 103 J/g,and the conversion efficiency E PT of photothermal enthalpy was about 40%.